Data from: Highly resolved early Eocene food webs show development of modern trophic structure after the end-Cretaceous extinction

Generalities of food web structure have been identified for extant ecosystems. However, the trophic organization of ancient ecosystems is unresolved, as prior studies of fossil webs have been limited by low-resolution, high-uncertainty data. We compiled highly resolved, well-documented feeding interaction data for 700 taxa from the 48 million-year-old latest early Eocene Messel Shale, which contains a species assemblage that developed after an interval of protracted environmental and biotal change during and following the end-Cretaceous extinction. We compared the network structure of Messel lake and forest food webs to extant webs using analyses that account for scale dependence of structure with diversity and complexity. The Messel lake web, with 94 taxa, displays unambiguous similarities in structure to extant webs. While the Messel forest web, with 630 taxa, displays differences compared to extant webs, they appear to result from high diversity and resolution of insect–plant interactions, rather than substantive differences in structure. The evidence presented here suggests that modern trophic organization developed along with the modern Messel biota during an 18 Myr interval of dramatic post-extinction change. Our study also has methodological implications, as the Messel forest web analysis highlights limitations of current food web data and models.现生生态系统的食物网（food web）结构共性已得到明确阐释。然而，古生态系统的营养组织（trophic organization）模式尚未厘清：此前针对化石食物网的研究均受限于分辨率偏低、不确定性较高的数据集。我们针对距今4800万年的早始新世（Eocene）最晚期梅塞尔页岩（Messel Shale）中的700个分类单元（taxa），编译了高分辨率、记录完备的取食相互作用数据集；该页岩所保存的物种组合，是在白垩纪末灭绝事件（end-Cretaceous extinction）期间及之后长期的环境与生物群变化过程中形成的。我们采用考虑结构随多样性与复杂度变化的尺度依赖性（scale dependence）的分析方法，将梅塞尔湖与森林食物网的网络结构与现生食物网进行了对比。拥有94个分类单元的梅塞尔湖食物网，其结构与现生食物网存在明确的相似性。尽管拥有630个分类单元的梅塞尔森林食物网与现生食物网存在差异，但这些差异并非源于结构本身的实质性不同，而是源自昆虫-植物相互作用（insect–plant interactions）的高多样性与高分辨率。本研究提供的证据表明，现代营养组织模式与现代梅塞尔生物群一同，在灭绝事件后长达18百万年（Myr）的剧烈变化时期中形成。本研究同时具备方法学启示价值：梅塞尔森林食物网的分析结果揭示了当前食物网数据与模型的局限性。